Recently, they've begun using gas up here in the boston, ma area that may contain up to 10 percent ethanol. I know some parts of the country have been using this for a while. Monday I went and mixed up a 2 gal can of mix. We always use 89 octane fuel, as recommended by just about every manufacturer. This particular mix was for Echo products, 50:1. So wednesday, I sold a backpack blower, went to fill it to prep it for the customer and it came out clear. My first though was god damn it, the guys in the shop must have used the rest and filled it with no oil. So i look down in the tank and there's a big black blob??? I shake the hell out of it and start to pour again and now it's normal. From Monday morning, till Wednesday afternoon, the oil seperated completely from the gas!!!!! This is insane!!! I can only imagine the ruined 2 stroke stuff that is going to come in because of this. I went and checked the other can for non echo and it was the same thing!!! I would recommend not mixing more than 2-2.5 gallons at a time and make sure the guys shake the cans. I'd hate to see guys wrecking equipment when they don't even know why. It's like being hit by a sniper! Also, we've seen more water in the fuel engine breakdowns lately. They claim this new blend of fuel will actually suck the moisture right out of the air. BE CAREFULL!!! Just a heads up.